DECT 6.0 Digital technologyInterference free for crystal clear conversations won't interfere with wireless networks and other electronic devicesProtect yourself from identity theft with digital security each call is digitized and encrypted, making it nearly impossible for someone to eavesdropAccessory handset only requires the DS6311 or DS6321 series phone to operate; no phone jack requiredCaller ID/call waitingHandset speakerphoneIntercom between handsetsConference an outside call between handsets200 Name and number phonebook directory easily store and dial frequently called numbersLarge lighted display for easier viewingBlue backlit keypad and displayVTDS6301